ZBrushCentral

ZBrush Problems - normal vs color map creation/projection bugs and smoothing

ZBrush Usage Questions
#1

hello there,

im having some trouble with zbrush
and id be glad if anyone could help me solve em otherwise i would have spent a whole week of my life for nothing learning zbrush and redoing things again and again due to its crashes… which would be a pity :stuck_out_tongue:

why does it crash all the time? sometimes i even have to start it 10 times in a row until it even gets to the starting screen?
got 2gb ram, 2x2Ghz Cpu, and 256mb ati 850x gfx card
not great but it should do the job

what step does the video maker in the tutorials for the max export do between subdividing and sculpting the tool?
at the end of the subdividing video he has an edgy, faceted look, on the start of the sculpting video the club is eventually all smoothed out like a 3dmax smoothgroup would look. How can i achieve that? (might solve the following problem)

how can i project a polypainted colormap/texture on my SubD1 model the same way zbrush projects the normal and cavity maps?
my problem is that the cavity/normal map and color map just dont match up in the end. i realized this is due to the fact that the color map gets projected on the high poly and the normal map gets projected on the low poly.
http://img223.imageshack.us/img223/8345/distq.jpg

3.1
i tried other methods to circumvent that by using a morph target (didnt help much) and using a cage (didnt help either), i then tryied using the subdivion with SMT (smooth) turned off to reatain the basic shape of my model which worked just fine and gave me a much better ability to paint where my paint belongs apart from the detail work
the problem here was that the normal maps generated that way aswell as the cavity maps showed the polygon edges of my original low poly model!
they had a faceted look which obviously wasnt what i wanted. How do i prevent that?
http://img196.imageshack.us/img196/7983/norm.jpg

3.1.1
i tried using the “import smooth groups plugin” therefore just to see it do absolutely nothing at all except that it activates “frame” on import…
(i use max 8)

3.1.2
i toyed around with the normal maps even more
having SMT turned off during subdivison allows you to create useful (meaning smoothed) normal maps only if you have just 2 subD levels… once you have 3 the normal map become all faceted again and thus unusable

4
why does zmapper sometimes not show the bottom frame with all the settings? a restart of zbrush helps but nothing else.

5
why does my paint tool sometimes stop drawing and only start again if i turn it to Zsub, draw abit, undo and then go back to Zadd or RGB?

rhetoric questions :roll_eyes:small_orange_diamond:

6
why does it crash so often?

7
why does it crash so often and without any sense? often on saving a tool (through the menu not the hotkey)

8
why does it not have a simple delete function that uses my DEL key instead of some awkward click and point adventure… thet mighty DEL button was an invention back in the middle of the last century which revolutionized the computer industry… just in case you missed it…

9
why cant i repickup somin when i leave edit mode? it makes using the canvas for somin else than drawing 2d pictures quite useless and gave birth to the annoying subtools thing… why not at least add objects that leave edit mode automaticly to the subtools list?

the greatest of thanx for anyone who can help me at least on the upper main questions…
these problems nearly made me cry… :cry: (ya its utterly sad if you see that you spent hours on hours creating somin you love and adore just to realize it was all pointless… kinda hillariously funny too but much more sad than a good laugh by now)

#2

I can’t speak for the crashes you’re experiencing, that’s something you should put the Pixologic support people. As for the questions you have about using the software, they seem like pretty standard beginner questions, so start with this:

http://www.pixologic.com/zclassroom/

#3

i watched these…
but neither they nor a text search on google nor this very page nor the online help could tell me how to smooth the faces of a model without distorting the whole mesh with catmull-clark in a way that the final normal map is not faceted like a bloody chessboard

actually everyone says it is impossible

but then in the classroom max video line the guy does exactly that… he subdivides a model with SMT off and in the next video you can see it has smoothed out faces whilst still having its edgy shape…
sadly the step where he applies this is lost somewhere in between both videos

but nevertheless this wouldne even be necessary if zbrush had the option to project textures/polypaint in exactly the same way as it does with normal and cavity maps… cause thats my main problem why i even started to work with SMT off… it outputs textures which are not matching the normal map like shown in the first screenshot i posted above…

#4

no this is not the problem dear dustin, i watched these videos and if you would have read my post youd have seen that i witnessed a behavior in these videos which would basicly solve my problem but this is no where documented, neither in this forum, the online help, any tutorial or post to be found on google nor anywhere else…

im talking about the missing step between “nomal maps for 3dsMax - Divided Subtools” and “normal maps for 3dsMax - Surfaces and Layers” (they are the same videos as for maya btw…)

in the end of “divided subtools” he has a model of a club which was subdivided with SMT off and has no smoothed faces (similiar to a max model WITHOUT smoothgroups, im not talking bout catmull),
in the next video “surfaces and layers” he has the very same model but it clearly has smoothed faces similiar to a model WITH smoothgroups in max (im again not talking bout the SMT on - Catmull clark “real” smoothing)

i need to know what this step is now as to be able to make a normal map for my low poly model, because if i just turn off SMT to retain the shape of my model during sculpting the output normal map becomes faceted and thus unusable,
the facet effect can be seen in the normal screenshot in my first post, it basicly makes a facet for each polygon of the original low poly model…

#5

I’m running a test on this right now. I don’t use Zmapper all that often…well, because it creates normals that don’t match the diffuse.

Anyway. I do all of my lowpoly baking in either XSI, MAX, or Xnormal. 2 good reasons to do this.
A. No real UV’s required until I even start the lowpoly model.
B. Avoid the problems that Zmapper creates…not being able to bake multiple objects, etc.

I’ll get back to you in a bit on the other things.

The delete key can do whatever you want it to…set up a hotkey for it.

#6

I can NOT recreate the problem you’re having. To me it appears to be a broken UV set up…either Zbrush did it, or max did. Try this.

Tool>texture>UV check.
See if you can see the wireframe in that texture.
also turn down the FS border.

If that does it then somewhere your UVs are broken…which is really what that looks like to me. But then again, like you said…you get fine normals if you have smt turned on. hmm.

Did you ever turn ON smt? That might be the problem…hmm…let me check that too.

#7

Nope…normals still come out fine.

What are your settings inside Zmapper?.

Oh yeah…as to Zmapper not having that bar.
what resolution screen are you using?
If the res is too small you need to close either 1 or both sidebars before going into Zmapper.

As to the crashes…I would send in a ticket to the support team for sure.
Crashing on saving is usually “user” error. or an Id10t error as they used to call it :stuck_out_tongue: Anyway. Always save at the lowest subD with all subtools. make sure no masks are active. Always save through subtool master (it does a check for hidden geometry and has a better save function). Also…don’t rush the saving. I can crash max everytime if I wait for the “autosave” to be running and then do something crazy like a boolean or a meshsmooth…yeah…real crazy. sigh.

Anyway, If you get back to this thread and still can’t figure out your normals I will make up a quick vid (gotta find my headset) and post it up.

#8

thx for checking into it
i really appreciate that :+1:

uv check displays a fine one piece mesh without problems… but ya my uv map is not perfect but i dont have overlapping or heavy distortions in it… imo zbrush should be fine with it

did another test now which slightly improves the situation:

i applied a mesh smooth in max before exporting with cubic output instead of classic or nurms (mesh smooth retains the original uv map layout but cuts the pieces, as long as you dont mess with it however it stays and can also be used for the un-meshsmoothed model)

did my test run:

-import low oly from max as *.obj (polygons, index 6, smooth groups activated)
-subdivide with SMT on to lvl 6
-draw a few grooves with rgb on
-col to texture
-export
-zmapper->cavity map
-export

overlay in photoshop

this is the result
http://img12.imageshack.us/img12/1101/dist2.jpg
black lines are the cavity and green (or red forgot :P) the color

it seems as if zbrush really needs perfect rectangulars to make a nice map or the distortion becomes less because the pre smoothed model matches the catmull smooth much closer than my original low poly

anyway this doesnt solve the actual problem (it would be a workaround but its still not perfect as you can see in the pic),
cause id like to turn SMT off to see where my actual edges are so i can draw some scratches on em, catmull just distorts the mesh too heavily

and the video i mentioned shows the use of it just not how to activate it

thats what happens in the video (normal maps to 3sdmax/maya subdividing mesh):

the club is low poly,
gets subdivided with SMT off
and eventually in the next video (layers and somin) it uses smoothing groups! (or somin that looks like it)
it retains its original shape whilst being smooth!

i tried a lot by now:P but everything i do with SMT off results in faceted normal maps like the picture in my first post shows

btw using the SMT off and on workaround doesnt really help…
if you turn off SMT for the first few steps (1-3 for example) and then activate it for the last subdivisions (4-6 for example) the model looks smooth in the viewport and retains much more of the shape than going fully SMTon but the created normal map still has facets, not as many or as heavy but they are still there…

anxiously awaiting a solution to it :laughing:

man if thatd somehow work i could even overlook the constant crashes… its just too much fun as long as it does what it should lol

#9

i used the presets of zmapper, actually all of em lol…
i even tried turning on and off all of the buttons i could find but to no avail, i always end up with these nasty facets,

could it be my computer? i doubt it actually but i can try to install zbrush on another mashine to check it…

as to the zmapper bar, i run at 1152x864 pixels
but that doesnt seem to be the problem (i read that thread too :P) imo as it usually works, just after switching between some tools and importing some more it eventually doesnt appear anymore, restarting zbrush tho solves that and i can see it again…
seems like a bug to me, dunno im not a real programmer lol

the crahses seem to be directly affected by the system memory… i can load and work on one tool with no problems but once i load a second and work on it everything becomes unstable,
starting zmapper causes a crash, saving a tool creates a crash, saving a document does…
sometimes zmapper even freezes my whole pc

the startup crashes are similiar affected by the memory it seems, if i have max and photoshop open at the same time it crashes much more frequently…

i assigned 1.5GB to zbrush tho (oreferences-mem-15xx-compact mem-saved settings) so basicly it should be fine with just one tool at 3million polies…

but ya i can live with that as long as i know when it crashes (not great but hey… live has flaws ;))… prolly need a new windows and more ram…
will try to compact mem after working on each tool next if i feel brave :stuck_out_tongue:

and thanx again for checking into this…
could you write down the steps you took to create a smooth normal map with SMT off please? or do you mabye even know the setting i have to activate or whatever might be the reason for my faceted normal maps?

#10

btw here is a picture of the tutorial videos i talked about which show a solution to my problem, just that it doesnt show how to achieve it :stuck_out_tongue:

http://img127.imageshack.us/img127/8157/smoothexample.jpg

#11

I’ll do up a vid in a bit.

And he went over it with the smooth brush. That’s now he got it smooth.

#12

that was one of my thoughts too and i tried it,

but if he had done so the tip and sides of the club would have been much smoother, if you look closely you can see that they are still “edgy”

in my tests the overall shape gets much more “rounded/smoothed” if you do the “smooth by hand trick”… the resulting mesh looks nearly as the catmull result does

also that would destroy the whole purpose of turning SMT off as the “manual smooth” uses the same algorythm afaik

here is an example of it:
http://img107.imageshack.us/img107/1254/smoothexample2.jpg
-left side red shows the basemesh subdivided with SMToff and not manually smoothed, the way i want it shapewise
-right side red shows the same mesh subdivided with SMToff but manually smoothed
-the blue overlay on the right side shows the same mesh subdivided with SMTon

thus i doubt that he actually did it that way…

#13

http://www.youtube.com/watch?v=S8ctKL-osf8

or embedded

//youtu.be/S8ctKL-osf8

#14

thx for all the effort to create this video :slight_smile:
its well done and the tooltips have a good placement

sadly it doesnt really solve the problem :cry:
as you can see in your video the normal map is basicly smooth but still each side of your club is getting its own smoothing, or in other words each side has a seperate smoothinggroup, is getting smoothed seperately

the problem with this is that once you hand your model with this normal map into a render program or a game engine in my case itll look like in my attachment pic from max

as you can see the polygons still become rather edgy due to this facetting effect, even though it is definately less edgy than without going halfway with- and half way without SMTon
but then going half way with SMT still changes the shape to some extent, not very heavy but it is there and thus will result in mimatching normal map vs color map (much less heavy than without tho)

i really dunno what to do atm lol… i need to finish this project and really dont want to paint all the detail by hand in photoshop lol, thats what i got zbrush for…

but even using the nvidia normal mapper (melody) results in these edgy normals… my max8 is totally useless for creating them as it cant really handle a multi million poly model anyway

edit:
before i send this in and wait another few hours for its posting lol here is my newest finding:

i just imported the high poly into max, not really usable but enough for a testrun

i applied the smooth modifier to recreate the smoothing groups but as i realized it still tstays edgy and doesnt look like my smoothed low poly…

this is due to the fact that smoothgroups smooth adjacent faces with each other, but once you subdivide you end up with alot more much smaller faces at the original polygon borders… this way it only smoothes the closest faces to these borders and not the whole original polygon planes and thus you end up with that edgy and faceted look

normal map smoothing probably works in the same way

no clue how to circumvent it atm :confused:

ill try to use a localized mesh decimation now and see if it helps if there are less faces…
oh god please ;D

Attachments

smoothexample3.jpg

#15

i think i forgot to actually attach the image in my last post, here it goes:

Attachments

smoothexample3.jpg

#16

workaround solution:

after some fiddeling i found a semi-solution, not really one but it helps alot:

1
create your low poly model in 3d max

2
uv map it

2.1
save it

3
add a meshsmooth modifier in max and set it to “Quad output” (instead of classic or nurms) (meshsmooth will change the uvmap but that wont affect the actual layout, you just get more seams)

4
export your model

5
import in zbrush

6
subdivide it with SMT on (the shape wont change drastically as you smoothed it yet before and meshsmooth seemigly uses a similiar algorythm)

7
sculpt and paint your detail

8
export your zbrush color, cavity, diplacement, normal map, etc

9
add the newly created textures to your “real” low poly model which you saved under 2.1

presto

due to the meshsmooth getting applied somehow the color and normal maps will match much better than simply subdividing your “real” low poly model which would get heavily distorted by the catmull-clark SMT
it will also still fit your “real” low poly model as it uses the same uv layout as your meshsmoothed one…

that method might also work for maya but my knowledge in there is just too limited to say for sure

i guess that might help all those people who experienced the same problem but never got an answer or one of dustinbrowns generic ones…
(ya i found some topics dealing with mismatching uvs)

thx goast666 for all your effort… it helped me understand the problem much better :slight_smile: and showed me that there is some helpful spirit in this community too… truly appreciated…

anyway it still doesnt solve the half-uselessness of subdividng with SMT off…
id really like to paint on my actual geometry instead of a geometry smoothed out model
this way SMToff is really just useful if you have a very simple shape which only has hard edges but not a mix between soft and hard

maybe a new algorythm for the whole painting process could be created which automaticly subdivides the areas around your sculpting/painting and leaves the rest untouched, might be a hell of a work to create it and maybe doesnt even work but this way normal maps could still come out smooth and unfacetted even if you used SMToff…
just a thought :stuck_out_tongue: as i said im not a real programmer…

using decimation master to reduce the polies outside your drawing area to allow the nomal map to smooth out the faces doesnt work as you loose your subdivision levels

#17

There is a fix for what you’re trying to do.

I didn’t realize you had rounded edges as well. And you can also break the “rounding” that Zmapper applies to a “flat” surface. I’ll do up another video in a little bit. (had to go buy a new headset, no idea where the other one went). Anyway, I’m gonna go get a beer.

Also, have you tried using Xnormal to create your normals? Or you can use max as well. You just have to decimate the mesh pretty far to get it into 8. well…you can do it buy breaking the mesh into 500k chunks or so. As soon as they get imported tell them to display as a box. Then import all of them, attach them all, and tell it to weld the borders with a .001 or .01. You bring in your lowpoly version and set up a render to texture to pull the normals from the actual highpoly. Max 8 can handle it…you just can’t see what the hell you’re doing when baking.

With dicimation master you can chunk the whole thing down into around 100-200K and retain enough detail that you can build a good projection cage and still see what is happening. As well as do your baking tests from the decimated version to check your raycasting distance and other things.

Once you have all those settings you then use the actual hires version to bake your maps. Or you just import those into Xnormal and tell it to bake them for you so you don’t have to deal with breaking your mesh into tiny chunks so you can get it into Max.

And I’m happy to help. Dustin is helpful as well, but when you see the same question a gizillion times you tend to say “look it up”. You seemed to have done that and still couldn’t find the anwser so I thought I’d help.

Anyway…off to the bar for me. I’ll get your video up later…and you can lay back and relax to the soothing sounds of my voice :stuck_out_tongue: HA.

#18

This headset sucks. I’ll make up a vid tomorrow.

#19

part 1

//youtu.be/YYMPO_5ThKQ

part 2

//youtu.be/Iq487iSCYGA